In the days before Iraq's defeat in the 1991 Gulf war, the vast sprawl of anonymous factory buildings that makes up the Badr General Establishment was a central hub in its efforts to design and build a nuclear bomb.

As Iraq has admitted to the United Nations, it was here, 20 miles south of Baghdad, that the bustling teams of technicians and machinists worked on components for the gas centrifuges and molecular pumps that were intended for Iraq's enrichment cascade for the fissile material for its nuclear bomb. It was here too that Iraq's missile technicians worked on modification and production of the Scud B missiles that they hoped would carry a warhead.

With Iraq's capitulation to the allied forces, Badr - like the State Enterprise for Heavy Equipment Engineering and dozens of other enterprises run under the auspices of the Ministry for Military Industrialisation - was supposed to be closed down and monitored under the UN ceasefire resolutions designed to dismantle Iraq's ability to retain, design and build weapons of mass destruction.

But the scientists and managers from Badr had different orders from Iraqi president Saddam Hussein. What they have been up to goes to the heart of US and UK concern that Saddam has been trying to assemble the expertise and materials to build weapons of mass destruction, for the men from Badr turned up at a factory in Minsk in the former Soviet republic of Belarus.The Iraqi delegation that arrived at the Belstroyimpex headquarters in July 1995 was a high-powered one, travelling under the aegis of the Badr General Establishment.

They carried a shopping list of high-specification machine tools, including diamond cutters, a powder-metal production line and a plasma-spray machine - all potentially components for nuclear weapons and a ballistic-missiles programme. The delegation was careful to cover its tracks, keeping the visit and the deals signed secret from the UN. Iraq went to greater lengths still to hide these purchases from the UN sanctions regime, smuggling them into Iraq via the Jordanian free port of Aqaba, and trying to hide the equipment once it reached Iraq.

The Iraqi deal with Belstroyimpex was not unique. As arms inspectors and independent researchers have established in the past two years, the deal was only a small part of an intensive effort by companies and organisations linked to the Iraq's Ministry of Military Industrialisation to acquire forbidden technologies and materials from Belarus and over a dozen other countries.

It is an effort, say diplomatic sources, that continued just two months ago, when Iraq's deputy Prime Minister, and Minister for Military Industrialisation, Abdul Tawab Mulla Howeish, was in Minsk to sign a new protocol authorising scientific and technical exchanges between the two states. Indeed as lately as 1998 - before their forced departure from Iraq - UN inspectors discovered machine tools delivered from Belarus at the Saddam Artillery Plant, where they found Iraqi technicians installing 14 new machines for manufacturing 75-millimetre lenses with a military use. The crates were marked 'Republic of Belarus, Vitebsk Machine Building Plant'.

The Iraqi activity in Belarus is the most worrying evidence that Iraq is still pursuing a covert procurement programme . It may not be the 'smoking gun' that proves that Saddam has acquired the fissile material to build his bomb, but it is evidence that he is trying hard.

Firm evidence exists that in the decade since the end of the Gulf war Saddam quickly rebuilt his secret procurement networks, casting his net from the UK to eastern Europe, South East Asia and as far as Africa, operating through a complex network of front companies and middlemen.

Iraqi agents have been active in Ukraine, Russia, Romania and in the former Yugoslavia. They have been spotted in Congo, Kenya, Jordan and Syria, in Malaysia and Indonesia. It has not always been a subtle or successful effort. Indeed some analysts say privately that the chaotic and piecemeal effort of Saddam's procurement network smacks of desperation. Its persistence is what is worrying Britain and the US.

And it is these procurement efforts that will provide the backbone of Tony Blair's dossier on the threat posed by Iraq when it is released this week. That dossier is likely to argue that Saddam's current efforts have strong parallels with the massive Iraqi procurement programme in the 1980s when Saddam began scouring the world to build his secret conglomeration of chemical, biological and nuclear-weapons factories.

'There has been an awful lot of background noise,' said one European diplomat. 'There is a lot of Iraqi procurement effort going on. Some of it is very inconclusive. But what is worrying is the accumulating evidence of the kind of stuff they have been - and continue to be - after. That has been a constant since the end of the Gulf war. It may not amount to evidence of a bomb, or a new missile system, but it is certainly evidence that they still desperately want it.'

A senior British diplomat in the region said: 'There has been concern that relations between Iraq and Ukraine and Belarus have been getting warmer over the last few months. There has been heightened activity and people going back and forth.' He said he had seen 'reports' from a variety of sources, including spies, of arms deals between the two nations and Iraq.

Among those deeply concerned about Belarus and Ukraine is Tim McCarthy, who served with the UN Special Commission on Iraq (Unscom) from 1994 to 1999 and completed 13 missions in Iraq, serving as deputy chief inspector for the missile team. Now a senior analyst at the Centre for Nonproliferation Studies in the US, he studied much of the available evidence about the Belarus connection.

'My concern was high about Belarus, for a number of reasons. One of the deals that the Iraqis have done was with the Minsk Tractor Factory. Public reports have stated that civilian tractors are produced. But it also produces missile launchers for Pakistan. The real [Belarussian] expertise comes with the missile launchers, and that is disconcerting to say the least.' McCarthy said Belarus had drawn up numerous agreements with Iraq. 'The equipment that Belarus had agreed to give Iraq would be considered to be a very real non-proliferation problem.'

Among the deals that most concerned him, however, was for a so-called plasma-spray machine used in anti-corrosion treatment of components used in nuclear weapons. 'The nuclear proliferation people were very concerned about that. We have very strong documentary evidence [about the deals]. It was production line stuff that would have been very hard for the Iraqis to acquire legally under the UN sanctions regime.'

At the head of Iraq's secret procurement effort is Abdul Tawab Mulla Howeish. A wiry and mustachioed military officer in his late forties - who also holds the rank of Deputy Prime Minister - Howeish, has come to be one of the most important figures in Saddam's regime, inevitably visible in every photo opportunity given by Saddam to Iraq's state-controlled media.

And it has been Howeish who has been most visible in recent Iraqi delegations to Belarus. It was his Ministry - under its previous head - that coordinated Iraq's massive secret procurement drive in the 1980s. The only difference, note inspectors who have been trying to unravel Iraq's new procurement programme, is that the names of the front companies - and the states prepared to deal with Iraq - have changed.

One of best assessments of Iraq's procurement effort has been supplied by former US weapons inspector Scott Ritter. Despite being one of the fiercest critics of the hawkish Bush line on Iraq, Ritter has noted the way in which Iraq set up a series of front companies in Jordan, Syria, Malaysia, and other countries that acted as official buyers of banned weapons and systems, which later found their way to Iraq.

'We [UN weapons inspectors] were following, in '97 and '98, information that held that Iraq was working very closely with the government of Syria to use Syrian procurement networks in place with Belarus, with Ukraine, with Russia. The Syrians would acquire military technology, military equipment, military hardware, in contracts between these nations and Syria, and then Syria would transfer this material to Iraq in a covert fashion. And the method of payment was Iraqi oil.'

Among companies that have already been revealed as being behind attempts to procure suspicious contracts are the Al Bushair trading company and the Al Saddirah Company - both identified in private memos by UN inspectors as the intermediaries in a number of deals to acquire banned technology in Belarus in the mid-to-late 1990s.

Among those who have compiled their own dossier on Iraq's new procurement networks are two American researchers, Gary Milhollin, director of the Wisconsin Project on Nuclear Arms Control in Washington, and Kelly Motz, of Iraq Watch, who published the 'Shopping for Saddam' report last year. Much of the evidence they collected was based, they say, on unpublished information collected by UN weapons inspectors detailing their suspicions about Iraq's continued efforts to hide a large-scale and covert rearmament programme.

'What [the research] showed is that Saddam's procurement network is alive and well and has been working steadily despite the sanctions,' said Milhollin. 'There are a lot of companies out there willing to break the embargo.'

Motz said: 'We are seeing everything from just some basic negotiations that probably didn't go anywhere once the firms figured out what was trying to be purchased to contracts that were actually implemented and goods that were found in Iraq by the inspectors. We have contracts for missile engine components, for guidance components for missiles. We actually found some high-end machine tools that are useful for making nuclear weapons, military goods such as [conventional] helicopters and aircraft which were clearly embargoed.'

At about the same time that the men from the Badr General Establishment were on their way to Belarus, UN inspectors uncovered further evidence of Iraq's secret procurement efforts - gyroscopes from dismantled Russian inter-continental ballistic missiles that were smuggled into Iraq, then dumped in a river when they were found to be incompatible with their missile systems. A second shipment of 115 gyroscopes was discovered in Jordan in October 1995.

What is clear is that despite consistent setbacks over the past eight years, Iraq's secret procurement effort is still active across the globe. Further evidence of this trend was supplied in the past fortnight. US Vice President Dick Cheney has added his own voice to the debate, claiming the US has intercepted efforts by Iraq to buy hundreds of highly machined aluminium tubes it says were destined for an Iraqi gas centrifuge enrichment system.

'You can say many things about what Iraq is up to,' said one diplomat familiar with the material. 'You can argue about what weapons he has, if any, how many, and if they will ever work. You can argue about whether he will takes two months or 10 years to build or acquire a nuclear bomb. But what you cannot argue with is the evidence that that Saddam has set up his secret weapons procurement network once again. That is the real worry.'